X5m f85 hollow exhaust sound

[Joey26]

Hey guys I was wondering if I can get some advise on my x5m f85
I'm running catless down pipes with stock muffler and I'm getting that hollow exhaust sound
I was wondering if there is anything I can do to make the exhaust sound deeper
I was thinking of adding secondary hi flow cats further down after the down pipes or perhaps adding some resonator?

Thanks

[Yiming]

http://f15.bimmerpost.com/forums/sho...0&postcount=39
He fixed it by switching to FI Exhaust, ask him for a sound clip

[gizmo958]

A good induction system or upgraded filters are good . without touching the exhaust it self